McALESTER, Okla. (AP) – The latest on the scheduled execution of Oklahoma death row inmate Richard Glossip (all times local):

12:30 a.m.

Oklahoma is preparing to carry out its first execution since a sharply divided U.S. Supreme Court upheld the state’s three-drug formula used in lethal injections.

Richard Glossip is scheduled to be executed at 3 p.m. Wednesday at the Oklahoma State Penitentiary in McAlester. He was convicted of ordering the beating death of a motel owner in 1997 in what prosecutors say was a murder-for-hire.

Glossip, 52, was the lead plaintiff in a case before the nation’s high court that argued the sedative midazolam violated the U.S. Constitution’s ban on cruel and unusual punishment because it didn’t adequately render an inmate unconscious before the second and third drugs were administered. The justices upheld the formula in a 5-4 opinion issued in June.

Glossip has maintained his innocence, and his attorneys filed a last-minute request for a stay of execution late Tuesday.